I came across an older colt 15rd. mag for 45 auto. it needed a little cleaning but is in good condition.

My questions is; Does anyone have experience with one of these magazines. I am haveing trouble feedin ammo into my 1911.

It will feed 3-4 rounds good and hang up on the 5th. I have to hand feed the next shell, and it will work again for 3-4 rounds.

Is this normal?

I came across an older colt 15rd. mag for 45 auto. it needed a little cleaning but is in good condition.

My questions is; Does anyone have experience with one of these magazines. I am haveing trouble feedin ammo into my 1911.

It will feed 3-4 rounds good and hang up on the 5th. I have to hand feed the next shell, and it will work again for 3-4 rounds.

Is this normal?

Not normal. The mag should feed smoothly for all 15 rounds. As you said "needs a good cleaning". It could have rough spots inside that hang the follower. Take it apart, clean and polish it's inards so the follower travels smoothly from top tp bottom. Also compare the lips at the top to a known good magazine, make sure it's not bent. Also make sure it engages into the mag well properly. Try holding pressure against the bottom as you shoot. By the way, I assume your 45 works fine with other mags?